Sàng nuyên tố - Vinoy 

void sieve(int N) {
    bool isPrime[N+1];
    for(int i = 0; i <= N;++i) {
        isPrime[i] = true;
    }
    isPrime[0] = false;
    isPrime[1] = false;
    for(int i = 2; i * i <= N; ++i) {
         if(isPrime[i] == true) {
             // Mark all the multiples of i as composite numbers
             for(int j = i * i; j <= N; j += i)
                 isPrime[j] = false;
        }
    }
}

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Python - Liệt kê tất các các chu trình trong đồ thị

graph = [[1, 2], [1, 3], [1, 4], [2, 3], [3, 4], [2, 6], [4, 6], [8, 7], [8, 9], [9, 7]] cycles = [] def main(): global graph global cycles for edge in graph: for node in edge: findNewCycles([node]) for cy in cycles: path = [str(node) for node in cy] s = ",".join(path) print(s) def findNewCycles(path): start_node = path[0] next_node= None sub = [] #visit each edge and each node of each edge for edge in graph: node1, node2 = edge if start_node in edge: if node1 == start_node: next_node = node2 else: next_node = node1 if not visited(next_node, path): # neighbor node not on path yet sub = [next_node] sub.extend(path) # explore extended path findNewCycles(sub); e
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